Suppressive Functions of Regulatory T Cells in Migraine

Migraine is a frequent, disabling condition, of great social and economical impact worldwide. This condition is more frequent in women and subjects with autoimmune and/or inflammatory diseases. Cytokine and immune cell dysregulations have been evidenced in migraine. Inflammation seems to play an important role in migraine chronification; however, the inflammatory mechanisms involved in migraine pathophysiology remain unclear. Regulatory T (Treg) cells play a central role in maintaining immune homeostasis. They regulate effector T (Teff) cell proliferation and cytokine production, through several suppressive mechanisms, such as the hydrolysis of adenosine triphosphate (ATP) into adenosine (ADO), mediated by surface enzymes Cluster Differentiation 39 (CD39) and Cluster Differentiation 73 (CD73). ATP is involved in pain processes in migraine, and insufficient hydrolysis could participate in pain chronification. Recent studies suggest altered proportions of Treg cells in migraine, and decreased levels of CD39-positive (CD39+) Treg cells, suggesting Treg suppressive functions may be decreased in the disease. However, there have been no functional studies to date to confirm this hypothesis. The investigators believe Treg suppressive functions may be decreased in migraine, and that such alterations may be caused by a malfunction in the ADO pathway.

Inclusion Criteria: * Females * 18 to 50 years old * Chronic migraine participants : chronic migraine (at least 15 days of headache/month, according to the International Classification of Headache Disorders, 3rd edition criteria Exclusion Criteria: * BMI \< or = 17kg/m² or \> or = 30kg/m² * Diagnosis or suspicion of type 2 diabetes, auto-immune or inflammatory diseases, immunodeficiency diseases * Diagnosis of headache of non-migraine origin, except for tension type headache \< or = 4 days per month (i.e.: cluster headache, post-traumatic headache, cerebral tumour…) * Pregnancy, delivery, miscarriage, breastfeeding, participation in a medically assisted human reproduction program (ovary stimulation/hormone therapy) \< 3 months before blood sampling * Menopause, hysterectomy, or bilateral oophorectomy * Flare of the autoimmune/inflammatory disease of interest \< 1 month before blood sampling * Modification of maintenance therapy for the autoimmune/inflammatory disease of interest (start, change of molecule, interruption) \< 3 months before blood sampling * Modification of prophylactic anti-migraine therapy (start, change of molecule, interruption) \< 3 months before blood sampling (for migraine participants) * Hormone therapy (besides contraception and treatment of endometriosis) * Transplantation (solid organ or bone marrow) * Cancer (active or remitting) \< 1 year before blood sampling (solid organ or blood) * Haematologic disease (benign or malignant) of the lymphoid lineage * Guardianship, curatorship, safeguard of justice or deprivation of liberty * For controls : diagnosis of migraine